Overview of memory: Definition of memory from a psychological perspective:
Part of cognitive psychology, memory is a process that involves preserving and retrieving information, past experiences and senses for future or present use (Sternberg R.J. & Sternberg K., 2012).
Stages of the memory process:
In a general concept, the process of memory involves three basic steps (encode, store, retrieve) in order to achieve a mental representation of an object or idea and the ability to recall that information.
http://www.simplypsychology.org/memory.html
Encoding: The process of converting tangible or physical senses experienced, into an associated memory. S. McLeod (2007) describes that the process of encoding can further be enhanced through visual, acoustic and semantic or meaning stimuli.
Storage: The means of maintaining information that was encoded into memory.
Retrieval: The ability and manner to acquire information that is stored.
Research has led to the discovery of the processes of memory functioning through extraordinary and deficient memory brain imagining due to the availability of countless studies that examine how individuals and their brains operate. Scientists and neurologists alike have detected various areas of the brain and their functions related to memory. This discussion is inteded to be an overview of important neurological structures and functions.
The brain is comprised of four lobes the frontal, occipital, parietal and temporal. Along the center of the brain, the Longitudinal Fissure divides these lobes into two hemispheres in which they then operate and control different functions of the body including the different forms of memory. Perhaps the most important structure within the brain is the hippocampus that originates from the limbic system and is involved in the memory process (Sternberg R.J. & Sternberg K., 2012). Its importance related to the processing of sensory memory is primarily due to the close proximity the hippocampus has with the amygdala which allows the olfactory cortex to process incoming scents more readily than that of the other senses. In addition, the amygdala is responsible for processes the emotional memories of individuals (Mastin, 2010).
The prefrontal cortex is the main neurological site involved during the formation of short-term memories that includes the central executive. The function of the central executive renders the control of the visual cortex and “phonological loop” also known as the feedback link during the process of communication. As assumed, the prefrontal lobe along with the frontal and parietal lobes of the brain help to establish the “neuronal communication” within short-term memory (Mastin, 2010).
Long-term memory absorbs the most information due to the processes that are involved in transferring short-term memory into long-term. Within the hippocampus, long-term memory is able to monitor and consolidate information coming in from short-term memory. The basic establishment of forming a memory into long-term storage is at the neural level, that is to say that at this stage in the memory process neurons experience a protein composition change that allow electrical excitation and communication with receptors to occur. After synapsing, reinforcement of memory is achieved. Encoding of declarative memories, the last subclass of long-term memory, begins at the medial temporal lobe with the help of various structures including the hippocampus and ends at the temporal lobe. Similar to declarative memory, semantic memory uses the frontal and temporal lobe for its activation. Beginning with the hippocampus, the episodic memory completes the pathway at the neocortex. Procedural memory, the most complex and involved memory, utilizes several structures to form its memory abilities (Mastin 2010). Significant figures:
Aristotle: “On the Soul”, one the earliest records that outline memory written by Aristotle approximately 2,000 years ago. Within his work he explains that all individuals who enter this world have a “tabula rasa” which means blank slate and that as humans we only gain memories or knowledge by experience. (Mastin, 2010).
HermanEbbinghaus: By studying his own mental processes through memorizing lists of nonsense syllables, Ebbinghaus was able to observe errors and response times it took for him to correctly reply back the syllables he learned. Through these observations, Ebbinghaus had coined the term rehearsal and would later find that repetition too helped to preserve and strengthen memory (Sternberg, R.J. & Sternberg K., 2012).
George A. Miller: In 1956, George Miller presented his concept of ‘chunking’, the amount of information that short-term memory can hold, that would later become a widely accepted model in the field of cognitive psychology and the forefront for all other theories pertaining to short-term memory. Through various experiments, George Miller concluded that individuals could only process and retain five to nine chunks of information which is more commonly known as seven plus or minus two or “The magical number seven”. (‘George A. Miller”, n.d.).
Endel Tulving: He was the first individual who noted a distinction between semantic and episodic memory in the 1970s. He noted that semantic memory is a general memory bank for world knowledge while episodic memory deals with personal events (Sternberg, R.J. & Sternberg K., 2012).
Eric Kandel: A recipient of the Noble Prize in 2000, Eric Kandel’s expertise and work lies within the field of both memory and learning. The ability to learn and recreate what was taught derives from the ability to make memories. By studying the behavior of sea slugs which only have a minuscule amount of never cells compared to that of humans, he was able to pin in on how sea slugs learned to modify their behavior in certain probing situations. The results of his experiments with the Aplysia also concurred with how the memory system functions. Differences at the biochemical level, namely the synapse level, were observed for both sea slugs and humans; changes within the synapse process render the formation memories. Kandel further encountered that short-term memory is triggered by changes in synapses versus long-term memory which is maintained by the stimulation of genes (“Eric Kandel”, n.d.).
George Sperling: His doctorial dissertation had led to the discovery of what is now known as iconic memory. The finding was made possible by flashing cards to participants with letters and symbols on a screen for fifty milliseconds. When the participants were asked to recall the location and type of symbol they saw, they could only report an average of four symbols (Sternberg, R.J. & Sternberg K., 2012).
Methods for measuring memory:
In order to understand how the process of memory works and what types of memory are involved, certain tasks are used to measure the capacity and capability of memory. Below are various methods that are used to test and measure memory:
Explicit-memory task: This form of memory task involves being able to recall specific information at the time it is requested. Falling within explicit-memory task, recall tasks require an individual to generate a fact or word from memory much like a fill-in-the-blank test. Free recall, serial-recall, cued-recall and more distantly recognition fall under the umbrella of recall tasks. Free recall consists of repeating a list of items at random order while in serial-recall, one is asked to repeat items of a list in the same order they were given. Within cued-recall the individual is given a pair of words in which one pair of the words is read aloud and other matching pair must be recalled by the individual. Recognition involves being able to distinguish correct answers out of a given problem set; this type of task is similar to a multiple-choice test (Sternberg, R.J, & Sternberg K. 2012).
Implicit-memory task: Being able to subconsciously infer and relay information is the key to this form of memory task. A common example of an implicit-memory task includes filling in missing letters from a word. Another means of studying implicit-memory is through tasks that test procedural memory, otherwise known to examine one’s ability to complete certain steps in a process that have been taught and previously learned by the individual (Sternberg, R.J, & Sternberg K. 2012). Types of memory:
There are three broad categories to the different types of memory sensory, short-term and long-term. These types of memory along with their corresponding subclasses are discussed below:
Sensory Memory: Lasting roughly around one-fifth to one-half of a second long, this form of memory is the shortest in length acting to mitigate incoming information from the various senses. The ability to remember a face or voice for abrief period of exposure is an example of sensory memory. Iconic memory, haptic memory and echoic memory are the subclasses of sensory memory that refer to visual stimuli, touch and auditory comprehension, respectively (Mastin, 2010).
Short-Term Memory: This type of memory is commonly referred to as working memory for its ability to hold a short span of information lasting roughly ten to fifteen seconds. Miller’s Law,a more widely accepted theory, concludes that on average seven random objects can be stored in short-term memory. Most participants through numerous experimental sessions were able to retrieve an average of five to nine items, the statistical median or the “magical number” was found in this experiment to be 7 ± 2 (Mastin, 2010). Common examples of short-term memory include, reading a sentence, completing a math problem and following directions.
Long-Term Memory: Is the ability to remember and store information from outside physical stimuli. The transition of memory from the short-term into the long term memory category can be explained by the process of consolidation (Mastin, 2010). Explicit and implicit memory are subclasses of Long-Term Memory. Information related to facts and events are held within explicit or declarative memory while implicit or procedural memory holds memories for completing steps for a certain task or skill. Lastly, declarative memory is broken down into (1) episodic memory, which signifies memory for time, place and emotions of a specific event, and (2) semantic memory, whichallocates memories for facts and meanings (Mastin, 2010).
catalog.flatworldknowledge.com
Key findings and their objections: Traditional Model of Memory vs. The Levels-of-Processing Model
These two theories stand for separate mechanisms of deriving to a memory or thought. Within the Traditional Model of Memory, Richard Atkinson and Richard Shiffrin created a three stage memory system for storage that brought insight into the workings of the psychological phenomenon. Their memory store can be broken down into: a sensory store, short-term store and long-term store. You may find this very similar to the different types of memory there are and that this because cognitive psychologists now refer to the three stores simply as sensory, short-term and long-term memory. Venturing away from this model is The Levels-Processing Model. This model states that no specific number or any number of “stores” is required but rather relies on the depth of encoding for memory. Essentially the amount of information and how it may be recalled depends on the way it was encoded into the memory system. Several findings including those from Craik and Tulving, 1975 and that of Zinchenko in 1962 and 1981 support the view for the latter of the two memory models (Sternberg, R.J, & Sternberg K. 2012).
Semantic and Episodic Memories as Distinct Systems?
Though Endel Tulving’s work in 1972 predicated a distinction between the two types of explicit memory it was still not clear if these memories were two distinct systems from one other. According to R.J. Sternberg, and K. Sternberg, these systems sometimes seem to function in dissimilar ways, other times the border between these memories became “fuzzy” and continuous support for methodology was unsteady. However, there has been support for two separate memories on the neurological level. Neuropsychological methods have shown a dissociation between the two memories with regards to retrieval. When one memory system is impaired in an individual the other is still capable of functioning. For instance those who suffer a traumatic brain injury may have smooth intellectual functioning versus someone who may have injured a different area of the brain and have significant impairment in the ability to communicate. Semantic and episodic memory are now favored as distinct systems from each other as the findings supported that one memory system can function without the other (Sternberg, R.J, & Sternberg K. 2012). Eyewitness Testimony Paradigm
One of the bigger and more prevalent issues within the study of cognitive psychology is eyewitness testimonies. Schacter took a closer look at how people have the tendency to distort memories. He came up with what he refers to as the “seven sins”. These “seven sins” are simply the ways in which people can distort information: Transience, Absent-mindedness, Blocking, Misattribution, Suggestibility, Bias and Persistence. This area of cognitive psychology still requires a great deal of research in order to establish a better means of identifying and trusting an eyewitness. Loftus for instance, conducted an experiment which demonstrated that participants were susceptible to distortion as an eyewitness (Sternberg, R.J, & Sternberg K. 2012).
The cause of excellent and poor memory systems:
Studies of people with superior and intact memory as well as those with decaying memory have helped to uncover the processes, types of memory and related functions of the brain involved.
According to R.J. Sternberg and K. Sternberg (2012), an individual who “demonstrates extraordinarily keen memory ability, usually based on using special techniques for memory enhancement” is referred to as a mnemonist. Their ability to funnel high volumes of insignificant information into significant events, perhaps done by the connection to the senses, permits them to process a large banquet of information. “S” and “V.P.” were two highly studied individuals in the mid to late 1900’s for their memory abilities. Using different mechanisms to recall and relay information, “S” was able to remember and cite information that was presented to him fifteen to sixteen years prior to being retested. “S” relied on visual imagery to remember information while “V.P.” used verbal translations to remember long rows and columns of numbers through dates (Sternberg, R.J. & Sternberg, K. 2012).
In contrast, many individuals suffer with disorders that cause memory impairment on a neurological level thus hindering different stages of memory; Common examples may include Aging, Autism, Dementia, Human Immunodeficiency Virus (HIV), Huntington’s Disease, Korsakoff’s Disease, Obsessive-Compulsive Disorder (OCD), Parkinson’s Disease, Schizophrenia, Stroke and Tourett Syndrome (Mastin, 2010). Amnesia and Alzheimer’s are also included in forms of memory loss; Individuals that have Amnesia, typically suffer from impairment of explicit or declarative memory. Alzheimer’s, which encompasses a multitude of symptoms including dementia and a progressive deterioration of memory, is more severe than Amnesia. Initially, this disease is observed by a gradual decline in episodic memory followed by a decrease in semantic memory (Sternberg R.J. & Sternberg, K. 2012).
This link provides a connection to the phenomenon of a young woman who encompasses the ability to recall memory of the past and further details the history of memory. The Mystery of Memory
University of Central Florida
EXP 3604c – Cognitive Psychology
Cynthia Quintana
Overview of memory:
Definition of memory from a psychological perspective:
Part of cognitive psychology, memory is a process that involves preserving and retrieving information, past experiences and senses for future or present use (Sternberg R.J. & Sternberg K., 2012).
Stages of the memory process:
In a general concept, the process of memory involves three basic steps (encode, store, retrieve) in order to achieve a mental representation of an object or idea and the ability to recall that information.
Encoding: The process of converting tangible or physical senses experienced, into an associated memory. S. McLeod (2007) describes that the process of encoding can further be enhanced through visual, acoustic and semantic or meaning stimuli.
Storage: The means of maintaining information that was encoded into memory.
Retrieval: The ability and manner to acquire information that is stored.
Memory related to the brain:
Research has led to the discovery of the processes of memory functioning through extraordinary and deficient memory brain imagining due to the availability of countless studies that examine how individuals and their brains operate. Scientists and neurologists alike have detected various areas of the brain and their functions related to memory. This discussion is inteded to be an overview of important neurological structures and functions.
The brain is comprised of four lobes the frontal, occipital, parietal and temporal. Along the center of the brain, the Longitudinal Fissure divides these lobes into two hemispheres in which they then operate and control different functions of the body including the different forms of memory. Perhaps the most important structure within the brain is the hippocampus that originates from the limbic system and is involved in the memory process (Sternberg R.J. & Sternberg K., 2012). Its importance related to the processing of sensory memory is primarily due to the close proximity the hippocampus has with the amygdala which allows the olfactory cortex to process incoming scents more readily than that of the other senses. In addition, the amygdala is responsible for processes the emotional memories of individuals (Mastin, 2010).
The prefrontal cortex is the main neurological site involved during the formation of short-term memories that includes the central executive. The function of the central executive renders the control of the visual cortex and “phonological loop” also known as the feedback link during the process of communication. As assumed, the prefrontal lobe along with the frontal and parietal lobes of the brain help to establish the “neuronal communication” within short-term memory (Mastin, 2010).
Long-term memory absorbs the most information due to the processes that are involved in transferring short-term memory into long-term. Within the hippocampus, long-term memory is able to monitor and consolidate information coming in from short-term memory. The basic establishment of forming a memory into long-term storage is at the neural level, that is to say that at this stage in the memory process neurons experience a protein composition change that allow electrical excitation and communication with receptors to occur. After synapsing, reinforcement of memory is achieved. Encoding of declarative memories, the last subclass of long-term memory, begins at the medial temporal lobe with the help of various structures including the hippocampus and ends at the temporal lobe. Similar to declarative memory, semantic memory uses the frontal and temporal lobe for its activation. Beginning with the hippocampus, the episodic memory completes the pathway at the neocortex. Procedural memory, the most complex and involved memory, utilizes several structures to form its memory abilities (Mastin 2010).
Significant figures:
Aristotle: “On the Soul”, one the earliest records that outline memory written by Aristotle approximately 2,000 years ago. Within his work he explains that all individuals who enter this world have a “tabula rasa” which means blank slate and that as humans we only gain memories or knowledge by experience. (Mastin, 2010).
Herman Ebbinghaus: By studying his own mental processes through memorizing lists of nonsense syllables, Ebbinghaus was able to observe errors and response times it took for him to correctly reply back the syllables he learned. Through these observations, Ebbinghaus had coined the term rehearsal and would later find that repetition too helped to preserve and strengthen memory (Sternberg, R.J. & Sternberg K., 2012).
George A. Miller: In 1956, George Miller presented his concept of ‘chunking’, the amount of information that short-term memory can hold, that would later become a widely accepted model in the field of cognitive psychology and the forefront for all other theories pertaining to short-term memory. Through various experiments, George Miller concluded that individuals could only process and retain five to nine chunks of information which is more commonly known as seven plus or minus two or “The magical number seven”. (‘George A. Miller”, n.d.).
Endel Tulving: He was the first individual who noted a distinction between semantic and episodic memory in the 1970s. He noted that semantic memory is a general memory bank for world knowledge while episodic memory deals with personal events (Sternberg, R.J. & Sternberg K., 2012).
Eric Kandel: A recipient of the Noble Prize in 2000, Eric Kandel’s expertise and work lies within the field of both memory and learning. The ability to learn and recreate what was taught derives from the ability to make memories. By studying the behavior of sea slugs which only have a minuscule amount of never cells compared to that of humans, he was able to pin in on how sea slugs learned to modify their behavior in certain probing situations. The results of his experiments with the Aplysia also concurred with how the memory system functions. Differences at the biochemical level, namely the synapse level, were observed for both sea slugs and humans; changes within the synapse process render the formation memories. Kandel further encountered that short-term memory is triggered by changes in synapses versus long-term memory which is maintained by the stimulation of genes (“Eric Kandel”, n.d.).
George Sperling: His doctorial dissertation had led to the discovery of what is now known as iconic memory. The finding was made possible by flashing cards to participants with letters and symbols on a screen for fifty milliseconds. When the participants were asked to recall the location and type of symbol they saw, they could only report an average of four symbols (Sternberg, R.J. & Sternberg K., 2012).
Methods for measuring memory:
In order to understand how the process of memory works and what types of memory are involved, certain tasks are used to measure the capacity and capability of memory. Below are various methods that are used to test and measure memory:
Explicit-memory task: This form of memory task involves being able to recall specific information at the time it is requested. Falling within explicit-memory task, recall tasks require an individual to generate a fact or word from memory much like a fill-in-the-blank test. Free recall, serial-recall, cued-recall and more distantly recognition fall under the umbrella of recall tasks. Free recall consists of repeating a list of items at random order while in serial-recall, one is asked to repeat items of a list in the same order they were given. Within cued-recall the individual is given a pair of words in which one pair of the words is read aloud and other matching pair must be recalled by the individual. Recognition involves being able to distinguish correct answers out of a given problem set; this type of task is similar to a multiple-choice test (Sternberg, R.J, & Sternberg K. 2012).
Implicit-memory task: Being able to subconsciously infer and relay information is the key to this form of memory task. A common example of an implicit-memory task includes filling in missing letters from a word. Another means of studying implicit-memory is through tasks that test procedural memory, otherwise known to examine one’s ability to complete certain steps in a process that have been taught and previously learned by the individual (Sternberg, R.J, & Sternberg K. 2012).
Types of memory:
There are three broad categories to the different types of memory sensory, short-term and long-term. These types of memory along with their corresponding subclasses are discussed below:
Sensory Memory: Lasting roughly around one-fifth to one-half of a second long, this form of memory is the shortest in length acting to mitigate incoming information from the various senses. The ability to remember a face or voice for abrief period of exposure is an example of sensory memory. Iconic memory, haptic memory and echoic memory are the subclasses of sensory memory that refer to visual stimuli, touch and auditory comprehension, respectively (Mastin, 2010).
Short-Term Memory: This type of memory is commonly referred to as working memory for its ability to hold a short span of information lasting roughly ten to fifteen seconds. Miller’s Law,a more widely accepted theory, concludes that on average seven random objects can be stored in short-term memory. Most participants through numerous experimental sessions were able to retrieve an average of five to nine items, the statistical median or the “magical number” was found in this experiment to be 7 ± 2 (Mastin, 2010). Common examples of short-term memory include, reading a sentence, completing a math problem and following directions.
Long-Term Memory: Is the ability to remember and store information from outside physical stimuli. The transition of memory from the short-term into the long term memory category can be explained by the process of consolidation (Mastin, 2010). Explicit and implicit memory are subclasses of Long-Term Memory. Information related to facts and events are held within explicit or declarative memory while implicit or procedural memory holds memories for completing steps for a certain task or skill. Lastly, declarative memory is broken down into (1) episodic memory, which signifies memory for time, place and emotions of a specific event, and (2) semantic memory, whichallocates memories for facts and meanings (Mastin, 2010).
Key findings and their objections:
Traditional Model of Memory vs. The Levels-of-Processing Model
These two theories stand for separate mechanisms of deriving to a memory or thought. Within the Traditional Model of Memory, Richard Atkinson and Richard Shiffrin created a three stage memory system for storage that brought insight into the workings of the psychological phenomenon. Their memory store can be broken down into: a sensory store, short-term store and long-term store. You may find this very similar to the different types of memory there are and that this because cognitive psychologists now refer to the three stores simply as sensory, short-term and long-term memory. Venturing away from this model is The Levels-Processing Model. This model states that no specific number or any number of “stores” is required but rather relies on the depth of encoding for memory. Essentially the amount of information and how it may be recalled depends on the way it was encoded into the memory system. Several findings including those from Craik and Tulving, 1975 and that of Zinchenko in 1962 and 1981 support the view for the latter of the two memory models (Sternberg, R.J, & Sternberg K. 2012).
Semantic and Episodic Memories as Distinct Systems?
Though Endel Tulving’s work in 1972 predicated a distinction between the two types of explicit memory it was still not clear if these memories were two distinct systems from one other. According to R.J. Sternberg, and K. Sternberg, these systems sometimes seem to function in dissimilar ways, other times the border between these memories became “fuzzy” and continuous support for methodology was unsteady. However, there has been support for two separate memories on the neurological level. Neuropsychological methods have shown a dissociation between the two memories with regards to retrieval. When one memory system is impaired in an individual the other is still capable of functioning. For instance those who suffer a traumatic brain injury may have smooth intellectual functioning versus someone who may have injured a different area of the brain and have significant impairment in the ability to communicate. Semantic and episodic memory are now favored as distinct systems from each other as the findings supported that one memory system can function without the other (Sternberg, R.J, & Sternberg K. 2012).
Eyewitness Testimony Paradigm
One of the bigger and more prevalent issues within the study of cognitive psychology is eyewitness testimonies. Schacter took a closer look at how people have the tendency to distort memories. He came up with what he refers to as the “seven sins”. These “seven sins” are simply the ways in which people can distort information: Transience, Absent-mindedness, Blocking, Misattribution, Suggestibility, Bias and Persistence. This area of cognitive psychology still requires a great deal of research in order to establish a better means of identifying and trusting an eyewitness. Loftus for instance, conducted an experiment which demonstrated that participants were susceptible to distortion as an eyewitness (Sternberg, R.J, & Sternberg K. 2012).
The cause of excellent and poor memory systems:
Studies of people with superior and intact memory as well as those with decaying memory have helped to uncover the processes, types of memory and related functions of the brain involved.
According to R.J. Sternberg and K. Sternberg (2012), an individual who “demonstrates extraordinarily keen memory ability, usually based on using special techniques for memory enhancement” is referred to as a mnemonist. Their ability to funnel high volumes of insignificant information into significant events, perhaps done by the connection to the senses, permits them to process a large banquet of information. “S” and “V.P.” were two highly studied individuals in the mid to late 1900’s for their memory abilities. Using different mechanisms to recall and relay information, “S” was able to remember and cite information that was presented to him fifteen to sixteen years prior to being retested. “S” relied on visual imagery to remember information while “V.P.” used verbal translations to remember long rows and columns of numbers through dates (Sternberg, R.J. & Sternberg, K. 2012).
In contrast, many individuals suffer with disorders that cause memory impairment on a neurological level thus hindering different stages of memory; Common examples may include Aging, Autism, Dementia, Human Immunodeficiency Virus (HIV), Huntington’s Disease, Korsakoff’s Disease, Obsessive-Compulsive Disorder (OCD), Parkinson’s Disease, Schizophrenia, Stroke and Tourett Syndrome (Mastin, 2010). Amnesia and Alzheimer’s are also included in forms of memory loss; Individuals that have Amnesia, typically suffer from impairment of explicit or declarative memory. Alzheimer’s, which encompasses a multitude of symptoms including dementia and a progressive deterioration of memory, is more severe than Amnesia. Initially, this disease is observed by a gradual decline in episodic memory followed by a decrease in semantic memory (Sternberg R.J. & Sternberg, K. 2012).
This link provides a connection to the phenomenon of a young woman who encompasses the ability to recall memory of the past and further details the history of memory. The Mystery of Memory
References
Eric Kandel. (n.d.). In Howard Hughed Medical Institute. Retrieved from http://www.hhmi.org/research/nobel/kandel.html
George A. Miller: Information Processing. (n.d.). In Theories of Learning in Educational Psychology. Retrieved from http://www.lifecircles-inc.com/Learningtheories/IP/GAMiller.html
Mastin, L. (2010). The Human Memory. Retrieved from __http://www.human-memory.net/index.html__
McLeod, S. (2007) Stages of Memory – Encoding Storage and Retrieval. Retrieved from __http://www.simplypsychology.org/memory.html__
Sternberg, R.J., & Sternberg K. (2012). Cognitive Psychology. Belmont, CA: Cengage Learning.
Multimedia References
Gray, E. & Schwarz, M. (2009) The Mystery of Memory. Retrieved from __http://www.simplypsychology.org/memory.html__
How Stuff Works. (2005). Basal Ganglia and Limbic System. [Diagram]. Retrieved from http://people.howstuffworks.com/swearing.htm/printable
McLeod, S. (2007). Stages of Memory [Chart]. Retrieved from http://www.simplypsychology.org/memory.html
Sochurek, H. (n.d.). [Photograph of a scanned brain]. Retrieved from http://www.guardian.co.uk/science/blog/2012/jan/10/put-memory-to-test-online-experiment
Stangor, C. (2010). [Chart of the different types of memory]. Retrieved from catalog.flatworldknowledge.com